National Oceanic and Atmospheric Administration official Blair Mase said wildlife workers spotted the dead whales on Sunday afternoon at Snipe Point, about six miles north of Sugarloaf Key.

That brings the overall death toll to 22.

The pod of 51 short-finned pilot whales was first spotted by a fishing guide on Tuesday in the shallow waters off a remote section of the Everglades. The species is one of the most commonly involved in mass strandings.

Mase said veterinary teams would try to determine whether disease was a factor in the deaths.

Officials do not know the status of the remaining whales. The marine mammals were last seen alive on Friday.